Multimodality Imaging in Inflammatory Cardiac Disease

Inflammatory cardiac diseases-including myocarditis, cardiac sarcoidosis (CS), infective endocarditis (IE), and pericarditis-have varied causes but share the need for precise diagnosis and management. Multimodality imaging is central: echocardiography (transthoracic echocardiography/transesophageal echocardiography) is universally first-line (especially for IE and pericardial effusion), while cardiac magnetic resonance imaging (MRI) provides gold-standard tissue characterization for myocarditis, CS, and pericardial inflammation. Computed tomography (CT) complements by delineating anatomy (eg valves, abscesses, pericardial calcification). Fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT) (and PET/MR) identifies active inflammation (metabolic uptake) in CS, myocarditis, and prosthetic IE but requires specialized patient preparation. Recent advances-updated Lake Louise Criteria incorporating T1/T2 mapping, PET suppression protocols, and hybrid imaging-have improved sensitivity and guided therapy. Each modality's strengths (eg echo's portability, MRI's tissue detail, PET's inflammation sensitivity) and limitations (eg echo's operator dependence, MRI contraindications, PET's false positives) must be understood. Here we review definitions, epidemiology, pathophysiology, and modality-specific applications; we compare diagnostic performance and provide practical algorithms, reporting standards, prognostic insights, and research gaps.